Swarm helps explain Earth's magnetic jerks

01 May 2019

Our protective magnetic field is always restless, but every now and then something weird happens – it jerks. Although scientists have known about these rapid shifts for some 40 years, the reason why they occur has remained a frustrating mystery, until now.

Since geomagnetic jerks were discovered in 1978 scientists have been trying to work out why the magnetic field suddenly and unexpectedly accelerates.